Knife-grinding machine



.l. DICK.

KNIFE GRINDING MACHINE. APPLICATION FILED DEC. 22, I919.

1,890,098,, PateutedSept. 6, 1921.

4 SHEETS-SHEET I- irrks J. DICK.

KNIFE GRINDING MACHINE.

APPLICAHSN FILED DEC. 22. 1919.

Patented Sept. 6, 1921.

4 SHEETS-SHEET 2.

I. DICK.

KNIFE GRINDING MACHINE. APPLICATION FILED DEC, 22. I919.

3 Wm M MA I Nu N. I Fr 3N 3% wh w w N J. DICK.

KNIFE GRINDING MACHINE.

APPLICATION FILED 050.22. I919.

UNITED stares PATENT creme. Q

JOSEPHDIGK, or C NTON, OHIO, Assrenon TO THE JOSEPH pron MANUFACTURING COMPANY, or CANTON, OHIO, A CORPORATION or onro.

' KNIFE-GRINDING MACHINE.

Specification of Letters Patent.

Patented Sept. 6, 1921.

Application filed. December 22, 1919; Serial No. 346,520.

zen of the United States, residing at Canton, in the county of Stark andSta-tejof Ohio, have invented certain new and useful Improvements in Knife Grinding Machines, of which the following is a specification.

This invention relates to a machine for grinding the beveled edge of straight knife blades used in fodder cutters, planing machines and the like, wherein a straight edge and a true bevel are necessary or desirable; and is an improvement upon the knife rinding machine disclosed in my former Fatent No. 1,199,672, of September 26, 1916. When such a knife is ground by applying it manually to the face of a grinding element, it is dflicult-if not impossible, to grind a straight edge and a uniform bevel, and when a supporting frame forthe knife is required to move endwise with respect to a relatively stationary grinding element, the machine requires so much space as to render it impractical or inconvenient for many kinds of use. A

The object of the present invention is to provide a grinding machine having a stationary carrying support for the knife and the grinding wheel moving longitudlnally thereof, with means for adjusting the knife support, means for automaticailv moving the grinding wheel to andfro endwise of the knife during the operation of the machine, and means for permitting the grinding element to operate; in a stationary position for use in ordinary work;

Ancillary features of the improvement relate to improved means for reversing the movement of the grinding element "at the ends of its reciprocation, and for holding the reversing means against accidental oper ation.

A preferred embodiment of the invention is illustrated in the accompany drawings forming part hereof in which Figure 1 is a front elevation of a knife grinding machine embodying the invention;

Fig. 2 a rearelevation of the same;

Fig. 3 a plan view of the same;

Fig. 4, a planview on an enlarged scale of the frame showing the channel rack bar in broken lines, the pendent cam lugs thereon in section, and the reversing mechanism in detail. H y i Fig. 5, an enlarged sectional view showing the clutch mechanism and the worm drive for the reversible rack;

, Fig. 6, a perspective view of the housing for the worm drive;

Fig. 7, a perspective view of the worm wheel;

Fig. 8, a similar view of the shaft upon which the worm wheel is mounted; and

Flg. 9, a similar view of the clutch member which engages the worm wheel.

Flg. 10 is a perspective View of one of the bell cranks and castings.

F 1g. 11 is a sectional view similar to Fig. 5, showing the clutch thrown out.

S milar numerals of reference refer to slmilar parts throughout the drawings.

The grinding machineincludes the frame 1, the cross heads 2 and 2 secured on the ends of the frame, the knife holder 3 secured by the adjusting arms 4 to the cross heads, slide bars 5 and 5 extending between and having their ends secured to the cross heads, the grinding head 6 mounted on the slide bars, the grinding wheel 7 havlng its spindle 8 journaled in the grinding head, the main pulley 9 on the main shaft 10, the belt gears 11 forthe grinding spindle, the worm 12 and worm wheel 13 for the clutch shaft 145, the clutch sleeve 15, the pinion 16 and the double faced reversing rack 17 which is mounted longitudinally on the frame.

The arms 4 for the knife support 3 are adjusted forward and rearward by means of screw heads 18 and the compression springs 19 located 011 these arms between the pendent bearings 20 and 20 on the cross heads, in which the arms are mounted; so that'the knife holder 3 may be adjusted to and from the edge 21, of the face of the grinding wheel and the springs will cushion the supporting arms in one direction. It will be understood that the work of grinding is performed by one peripheral edge only of the grinding wheel, in the manner well known in the art, the knife 22 being secured to the support 3'by the clamps 23. For this reason the spindle 81of the grinding wheel is located at a slight angle from normal t the support 3. i

The main shaft 10 is journaled in the bearing 26 secured in fixed relation to the frame substantially midway between the ends thereof and power received by this shaftfrom 'themain' pulley 9 is transmitted to the grinding spindle 8 by means of the belt 11 which passes around the pulley 27 on the main shaft, the pulley 28 on the grinding spindle and the idle pulleys 29 and 30 journaled on the oscillating arm 31,- which rises from a bearing journaled on the main shaft. r

The upper end of the oscillating arm 31 is bent L-shaped to the side opposite the grinding spindle 8, with which spindle it is connected by the link 32 pivoted at one end to the grinding spindle and at the other end to the angle of the L-shaped arm 31 between the pivots of the idle pulleys thereon, as set forth more fully in my former patent. .The construction and arrangement of these partsserves to carry the idle pulleys 29 and 30 in proper relative position to hold the belt 11 taut in all the varying positions of the grinding spindle as it moves to and fro with the grinding head upon the slide bars.

' Power is transmitted from the main shaft 10 by the belt above described and the worm .12 to the clutch shaft 14 upon which is fixedlymounted the pinion 16 arranged to mesh alternately with the racks 34 and 35 which face each other on the flanges of the channelbar 17. The clutch shaft 14 is journaled through a bearing portion 36 in'the base plate 37 of the grinding head 6, and a pin 38 is located through said shaft and protrudes beyond the shaft on each side, just above the bearing portion 36, for the purpose of supporting the shaft on the bearing.

The worm wheel 13 which meshes with the worm 12 is rotatably mounted upon the shaft 14 and is preferably hollowed upon its under face as shown in the sectional portion at 39 in Fig. 5 in order to; accommodate the pin. 38. A clutch face, comprising the inclined teeth 40 is provided upon the upper side of the worm wheel 13 and these clutch teeth are arranged to mesh with the clutch teeth 41 upon the lower end of the clutch sleeve 15, said clutch sleeve being mounted upon the clutch shaft 14 and provided with an elongated vertical slot 42 which receives the protruding end of a pin 43 carried by the clutch shaft 14 near its opposite end.

The clutch sleeve 15 is journaled in the bearing portion 45 of the housing 46 and is provided upon its upper end with a hand wheel 47. The housing 46 is secured on the base plate 37 and the bearing 45 is provided with a plurality of longitudinal slots, arrangedto pass the stud 49 upon the clutch sleeve 15, and on its upper end with the radial depressions 50 arranged to receive the stud 49 when it is desiredto hold the clutch sleeve 15 out of-engagement with the clutch teeth uponthe worm wheel 13, in order to permit the grinding wheel'tooperate in a stationary position for usein ordinary work. Stops 51 and 52 are provided upon each side of the depressions 50 to prevent the stud 49 from being accidentally displaced when. the clutch member 15 is thrown out or in the raised position. ,So as to more readily seat the stud 49 in the depression when it has passed over the other stop one of the stops for each depression is preferably extended higher than the other.

The channel rack bar 17 is mounted for transverse movement upon the frame, the ends of said rack bar being slidably received within suitable bearings 53, in the cross heads 2 and 2 and one or the other of the racks 34 and 35 is always held in engagement with the pinion 16 upon the clutch shaft 14. V

The racks 34 or 35 are held in engagement with the pinion 16 by means of the bell crank levers 5'5 and 55 which are pivotally mounted upon pintles 56 and 56 respectively carried by the bearing plates 57 and 57 respectively secured on the frame 1 of the machine. Eachof the bellcrank levers provided with an arm 58 and an arm 59, i

the arms 58 bein arranged to engage the pendent cam lugs 60 upon the rack bar to hold the rack 34 in engagement with the pinion16 and the arms 59 being arranged to engage the pendent cam lugs 61 to hold the rack 35 in engagement with the pinion 16. A link 62 is pivoted to the frame at 63 and to the double rack bar 17 at 64 to hold the rack bar from endwise movement as it slides? bodily transverse the frame.

Each of the bell crank levers is provided with a third arm 65 having a pendent pin 66 thereon, said pin being arranged to ride down over the beveled edges 67 of the adjacent bearing plate, at'the end of each operation, to prevent the bell crank lever from being accidentally displaced from the jarring of the machine when either one of the racks is engaged with the pinion 16.

A trip bar 68 is slidably mounted in suitable bearings 69 and 69'. formed upon the heads 2 and 2 respectively,said trip bar being provided with a pair of spaced pins 70 and 70 near each end portion thereof arranged to engage the adjacent pin 66 to throw the bell cranks into either position.

A spring 71 is connected at one end to the frame as shown at 72 and at its other end is pivotally connected to a link 73, said link be ing pivotally attached as at 74 to the trip bar 68. As the trip bar is moved longitudi nally in either direction the spring 71 and link 73 will cause it to be thrown quickly to the limit of its movement the instant the link passes over its pivotal center 75.

A pair of spaced tappets 76 and 76 are mounted upon the trip bar and arranged to be engaged bythe pendent flange 77-on the base plate 37 as it reaches each endof' its movementsliding the trip bar withit until the link 73 passes over its pivotal center when the spring 71 will cause the trip bar to complete its movement in that direction. The pins 70 and 7 0 upon the trip bar engage the pins 66 upon the bell cranks, throwing the bell cranks into the reverse position, sliding the double rack bar 17 transversely across the frame, and bringing the opposite rack thereon into engagement with the pinion 16.

When the grinding head is carried by the rotation of the pinion 16 upon either rack 34 or 85 toward one end of the frame, the knife which is clamped to the knife holder 3 will be ground along its entire edge and as the grinding head reaches the limit of its move ment in this direction the reversing mechanism above described will be operated, causing the grinding head to move in the opposite direction toward the other end of the frame where the reversing action is repeated.

In the operation of the machine; when it is desired to grind the knife blades such as shown at 22 in Fig. 1, the tappets 76 and 76 are properly adjusted upon the trip bar to cause the grinding mechanism to be reversed when the grinding wheel reaches each end of the knife. Power is transmitted from the main shaft 10 through the belt 11 to the spindle 8 and through the worm 12 thereon to the worm gear 13 upon the clutch shaft 1&.

When it is desired to move the grinding head automatically longitudinally upon the frame and automatically reverse the direction thereof at each end of its travel, the clutch sleeve 15 is moved into its lowered position as shown in Fig. 5 coupling the worm gear 13 to the clutch shaft 14 by means of the teeth and 41, the pinion 16 which is fixed to the clutch shaft engaging one of the rack faces of the rack 17 causing the grinc ing head to travel longitudinally upon the frame until the pendent flange 7 7 upon the grinding head engages one of the tappets 76 and 7 6 moving the trip bar 68 longitudinally with the grinding head, bringing the pins 70 Or 7 0 into engagement with the depending studs 66 upon the bell cranks, oscillating said bell cranks, and causing the arms 58 or 59 thereon to be moved into engagement with the depending cam lugs 60 or 61 upon the rack 17, the link 73 as it passes over its pivotal center being actuated by the spring 71, to quickly throw the trip bar 68 into either extreme position, thus quickly throwing the bell crank into the reverse position.

As the bell cranks are thus reversed and thrown into engagement with the pendent cam lugs 60 or 61, the rack 17 is bodily moved transversely across the frame bringing the opposite rack face into engagement with the pinion 16 causing the grinding head to be moved longitudinally in the reverse direction until the dependent flange 77 thereon engages the other tappet when the reverse action above described is repeated.

For ordinary grinding, where it is desired to maintain the grinding head in fixed position in order that the periphery of the grinding wheel may be used, the clutch sleeve 15 is raised as shown in Fig. 11, the stud as be ing passed through one of the slots 48 and seated in the adjacent recess 50, thus uncoupling the worm gear 13 from the clutch shaft and allowing it to rotate idly thereon, the grinding wheel being rotated continuously through the belt 11.

1. A grinding machine including a frame, a work holder at one side of the frame, a grin-ding head mounted on the frame for longitudinal movement parallel with the work holder, spaced connected facing racks mounted for transverse movement on the frame, grinding mechanism mounted on the head including a pinion between the racks, and means for bodily moving the racks transverse the frame to engage either one of the racks with the pinion. V

2. A grinding machine including a frame, a work holder at one side of'the frame, a

grinding head mounted on the frame for.

longitudinal movement parallel with the work holder, spaced connected facing racks mounted for transverse movement on the frame, grinding mechanism mounted on the head including a. pinion between the racks, means for bodily moving the racks transverse the frame to engage either one of the racks with the pinion, and means actuated by the movement of the head for bodily moving the racks transverse the frame to engage the other one of the racks with the pinion.

8. A grinding machine including a frame, a work holder at one side of the frame, a grinding head mounted on the frame for longitudinal movement parallel with the work holder, spaced connected facing racks mounted for transverse movement on the frame, grinding mechanism mounted on the head including a pinion between the racks, means for bodily moving the racks transverse the frame to engage either one of the racks with the pinion, and means for disengaging the pinion from the grinding mechanism.

OSEPH DICK. 

